Mold for making combination roller and shaft



Jan. 9,1968

E. W. FERDIG MOLD FOR MAKING COMBINATION ROLLER AND SHAFT Original FiledOct. 15, 1962 5 ShetsSheet 1 INVENTOR 424 Wilma/6 Jan. 9, 1968 E. w.FERDIG 3,362,675

MOLD FOR MAKING COMBINATION ROLLER AND SHAFT Original Filed Oct. 15,1962 5 Sheets-Sheet 2 INVENTOR. Z/\\ 54,42 W/z'Av/a 2627 BY i wlw4770/?IVEVSY Jan. 9, 19.68 E. w. FERDIG 3,362,675

MOLD FOR MAKING COMBINATION ROLLER AND SHAFT Original Filed Oct. 15,1962 5 SheetsSheet 5 I Q INVENTOR. l i-ig BY [41% W/zw/a zmm UnitedStates Patent 3,362,675 MOLD FOR MAKING COMBINATION ROLLER AND SHAFTEarl W. Ferdig, Burbank, Califi, assignor to George F. McMnrray, LosAngeles, Calif., an individual Qriginal application Oct. 15, 1962, Ser.No. 231,328, new Patent No. 3,206,992, dated Sept. 21, 1965. Divided andthis application Jan. 4, 1965, Ser. No. 423,145

11 Claims. (Cl. 249129) ABSTRACT OF THE DISCLOSURE A mold having a bodyprovided with a hole and an annular wall disposed within the hole. TheWall includes circular annular recesses for simultaneously molding aroller provided with an axial bore and a shaft provided with annularflanges of a diameter greater than the diameter of the axial bore.

This invention relates to roller assemblies and method and apparatus formaking them, and is a division of my copending application Ser. No.231,328 filed Oct. 15, 1962, now US. Patent No. 3,206,992.

This invention has many different uses, such as in wheels, bearings, andthe like, but is specifically described with reference to its use as apulley for drapery pull cords.

There is a large demand for an inexpensive roller which can be used as awheel, bearing, pulley, and the like. In the past, such rollers havebeen made by separately molding plastic rollers and shafts, andthereafter assembling the molded parts. The disadvantage of such rollersand the procedures for making them is that the various parts must becast and handled separately, and the assembling step is time-consumingand expensive.

This invention provides a plastic roller assembly which is cast in asimple mold and ejected from the mold ready for immediate use, i.e., theroller is cast around the shaft to be rotatable on it, and yet be lockedagainst longitudinal movement to prevent the roller from sliding off theshaft.

Briefly, the invention includes a plastic roller having an axial openingthrough it. A plastic shaft is disposed through the opening in theroller, and a pair of outwardly extending flanges are formed integrallyon the shaft on opposite side of the roller. The effective outerdiameter of each flange is greater than the effective diameter of theaxial opening through the roller to prevent the roller from slipping offthe shaft. Preferably, an annular longitudinally extending lip is formedon the periphery of each flange to increase its rigidity and strength inresisting longitudinal movement of the roller along the shaft.

In one presently preferred embodiment of the invention, the shaftincludes a longitudinal opening through it to facilitate mounting of theroller in various installations, e.g., as pulleys for drapery pullcords. In the preferred form of the invention, the roller includes aplurality of inwardly extending longitudinal projections or spokesradially spaced around the axial opening throughrit. The inner portionsof the ribs define the effective diameter of the axial opening. When theroller is to be used as a pulley, its outer periphery is concave toreceive and restrain a cord, or the like.

To form the outwardly extending flanges on the shaft which limit thelongitudinal movement of theroller on the shaft, the mold for castingthe roller of this invention requires undercut cavities which ordinarilywould involve an expensive mold of many different parts to facilitateremoval of the cast product. This invention provides a unique. methodfor removing the cast roller assembly from a relatively simple mold,even though the flanges extend transversely to the direction of removalfrom the mold.

Briefly, the method includes pouring molten plastic into a mold to forma roller having an axial opening through it, and to form a shaftdisposed within the opening. The shaft has outwardly extending flangeson opposite sides of the roller opening, and the flanges have a greatereffective diameter than that of the axial opening. The plastic in themold is cooled to a state being solid and having some degree ofelasticity. While the plastic is still hot and elastic, the shaft androller are stripped from the mold so that the flanges can be resilientlydeformed to release from the mold and then return to their original castpositions. Thereafter, the plastic cools to a further hardened state sothat the roller cannot be removed from the shaft without rupturing theplastic material.

The mold for casting the roller assembly includes a body which defines ahole. An annular inner wall is disposed Within the hole to be in contactat its ends with the body and to be disposed around the central portionof the hole to form a longitudinal shaft cavity. The surface of the holehas a first undercut recess located beyond one end of the wall. Thefirst recess communicates with the hole and extends outwardly past theinner wall. The surface of the hole also has a second undercut recesslocated beyond the other end of the wall. The second recess communicateswith the hole and extends under and outwardly past the inner wall toform the second flange cavity. The first and second recesses form firstand second flange cavities, respectively. An outer annular wall isdisposed around the space beyond the inner wall to define an annularroller cavity between the two walls.

In the preferred form of the mold, each flange cavity is annular and isjoined at its respective periphery by a separate longitudinallyextending annular recess for forming the reinforcing lip on each flange.Preferably, the annular inner wall is relatively thin with a pluralityof radially spaced and outwardly extending longitudinal projections. Thewall is as thin as is practicable, because the thickness of the walldefines the play between the shaft,

and the roller. The longitudinal projections on the outer portion of theinner wall provides ribs to strengthen the inner annular wall withoutincreasing the play between the shaft and roller in the final product,because the spokes of the roller are molded between the ribs on theinner wall. Preferably, the outer wall of the mold is convex, so thatthe periphery of the roller is concave. The mold also includes a fillingchannel through the body to discharge into the hole and, preferably, theinner wall includes an opening through it to provide a flow passage ofplastic from the outer to the inner portion of the mold.

Conveniently, the mold is formed from a pair of blocks having opposedsurfaces. Longitudinal openings in each block open out of the opposingsurfaces to form the mold hole when the surfaces are held together.Movable split plates with a circular opening having a convex wall areused to form the outer wall. Movable pins are disposed in each block toextend into the recesses which form the mold hole to define alongitudinal opening through the shaft, and provide means for ejectingthe cast assembly from the mold.

These and other aspects of the invention Will be more fully understoodfrom the following detailed description and the accompanying drawings,in which:

FIG. 1 is a plan view, partly broken away, of the presently preferredembodiment of the invention;

FIG. 2 is an elevation, partly broken away, of the roller assembly shownin FIG. 1;

FIG. 3 is a perspective view of the mold used to form the rollerassembly shown in FIGS. 1 and 2;

FIG. 4 is a view taken on line 4--4 of FIG. 3 g

FIG. 5 is a view taken on staggered line 55 of FIG. 4;

FIG. 6 is a View taken on staggered line 6-6 of FIG. 4;

FIG. 7 is a view taken on line 7-7 of FIG. 5;

FIG. 8 is an exploded perspective view of the two plates which form theouter annular wall in the mold; and

FIG. 9 is an elevation of an altenate embodiment of the invention inwhich the periphery of the roller is convex instead of concave.

Referring to FIGS. 1 and 2, an annular roller 10 has a longitudinalaxial opening 11 in which is disposed an annular shaft 12 having alongitudinal central bore 13 through it. Preferably, both the shaft andthe axis are made of a plastic which i easily molded under heat andpressure. Nylon and phenolic condensation products are especiallysuitable because as they cool from a molten to a rigid state, they gothrough a phase in which they are solid and yet relatively elastic. Thisfeature is particularly important in releasing the roller-shaft assemblyof this invention from a simple mold, as is explained in detail below.

The inner periphery of the roller includes a plurality of radiallyspaced and longitudinally extending projections or spokes 14, the innerfaces of which define the effective diameter of the longitudinal opening11 through the roller. The spokes are formed integrally with the rollerin a molding operation subsequently described. The outer periphery ofthe roller is concave to form an annular groove 15 which is particularlyuseful when the roller assembly is used as a pulley, or the like.

A separate outwardly extending flange 16 is formed at each end of theshaft. The effective outside diameter of each flange is substantiallygreater (as shown in FIG. 2) than the effective internal diameter of theroller. Thus, the roller cannot slide longitudinally off the shaftbecause the inwardly extending spokes would engage the inside surfacesof the flanges. As best shown in FIG. 1, each flange includes anintegral annular lip 17 which extends longitudinally away from theroller and adds strength and rigidity to the periphery of each flange.

The bore 13 through the shaft facilitates mounting the assembly byconventional bolts, rivets, and the like. As the roller is subjected toa load, say, a drapery pull cord (not shown) the roller slides aroundthe shaft, the inner ends of the spokes acting as bearing surfacesagainst the outside of the shaft. As shown in FIG. 2, the clearancebetween the shaft and the spokes is less than half the distance that theshaft flange overlaps the spokes, so that even when the roller is loadedtransversely to force the spokes on one side against the shaft, theflanges still overlap the spokes around the entire periphery of theflanges to prevent cocking or jamming of the roller.

FIGS. 38 show a mold 20 for forming the roller assembly shown in FIGS. 1and 2. The mold includes first and second rectangular blocks 21 and 22,respectively, adapted to be moved toward and away from each other in thedirections shown by arrows 23 in FIG. 3. The movement of the block ispreferably achieved by conventional automatic means (not shown).

A stepped bore 24 extends through the first block 21 in a directionnormal to an interior flat surface 26, which faces toward a flat surface27 on the second block 22. The stepped bore 24 includes a relativelylarge section 28 opening out of the surface 26. A first inwardlyextending shoulder 29 is formed between section 28 and section 30 of thestepped bore 24. A second inwardly extending shoulder 31 is formedbetween section 30 and section 32 of the stepped bore 24. The section 32opens out of a surface 33 opposite from interior surface 26 of the firstblock. An annular first mold insert 34 makes a close fit in the steppedbore 24 and bottoms against shoulders 29 and 31. A longitudinal bore 35extends through the first mold insert, and is slightly larger than andcollinear with the reduced section 32 of the stepped bore 24. A firstejection pin 36 makes a close sliding fit in the bore 35 of the firstmold insert. The end of the first ejection pin adjacent the second blockis of reduced external diameter and has a flat face 38 which normally isin the plane of the contiguous surfaces 26 and 27 when the first andsecond blocks are fitted together as shown in FIG. 4. As shown best inFIG. 7, a thin annular wall 44 is formed integrally with the end of thefirst mold insert adjacent the second block. The remote end of the firstannular inner wall is flush with the normal position of the flat face 38of the first ejection pin. A plurality of radially spaced andlongitudinally extending ribs 42 are formed integrally around theoutside surface of the first annular inner wall. The end of each ribadjacent the first mold insert includes an outwardly extending foot 44with an outer convex surface portion 45 shaped so that a concave surfaceportion 46 is formed between adjacent feet 44. The ribs and feet of themold form the spokes and spaces between their adjacent ends, as shown inFIG. 1.

A first annular undercut flange recess 48 (FIG. 7) is formed in thefirst mold insert to open into the longitudinal bore 35 extendingthrough the insert. A first annular lip recess 50 communicates with theouter periphery of the first flange recess and extends longitudinallyaway from the thin annular wall. The first flange recess and itsadjoining longitudinal recess form one flange and lip on the shaft shownin FIGS. 1 and 2. Moreover, the recesses 48 and 50 are located outwardlyof the outside diameter of the thin Wall 40, the thickness of whichdetermines the annular space 18 between the shaft and effective internaldiameter of the roller. Thus, the flange and its associated lip formedby recesses 48 and 50 are outwardly of the inner limits of the spokes 14shown in FIGS. 1 and 2. It is this feature which prevents the rollerfrom slipping longitudinally off the shaft.

As shown in FIG. 5, a pair of plates 52 are disposed to be movabletoward and away from each other in a guide groove 53 formed in thesurface 26 of the first block. In the position shown in FIG. 5, theinner edges 53A (FIG. 8) of plates 52 abut along a line passing throughthe center of the stepped bore 24 through the first block. Referring toFIG. 8, the inner edges of each plate include a semi-circular recess 54which form an outer annular wall 56 around the inner annular Wall whenthe plates are pushed together as shown in FIG. 5. Preferably, theannular wall is convex inwardly to form the annular groove 15 in theroller as shown in FIG. 2.

Liquid plastic is injected into the mold through a filling opening 57which extends from the outside surface .33 to open into the bottom ofthe guide groove 53 in the first block. With the plates in the positionshown in FIG. 5, and particularly in FIG. 7, a passage 58 in the bottomof one of the plates 52 overlies the filling opening 57. The passage 58opens through an inclined channel 60 through the outer annular wall andinto the mold hole. A flow opening 62 (FIG. 7) in the thin annular wallon the first mold insert permits plastic to flow into the space withinthe inner annular wall.

The second block 22 is virtually a mirror image of the first block, andtherefore is not described in detail. It includes a second mold insert64 with a thin inner annular wall 65 that abuts the inner annular wall40. A second ejection pin 66 makes a close sliding fit within alongitudinal bore 67 of the second mold insert. The second thin annularwall 65 does not include a flow opening because the flow opening in thefirst annular inner wall is adequate. A second annular flange recess 68is formed in the second mold insert and opens into a longitudinallyextending lip recess 70 to form a flange and lip identical with thoseformed by recesses 48 and 50 in the first mold insert. A rectangularrecess 72 in the insert surface 27 of the second block is formed aroundthe second mold insert to hold the plates 52 firmly in the positionshown in FIGS. 4, 5, and 7 during the molding operation. The secondinner annular wall also includes radially spaced and longitudinallyextending ribs 77 which are identical with those formed on the firstannular inner Wall. The two mold inserts are each locked in properrotational orientation with respect to each other by keys 73 incollinear bores 74 in each of the blocks. Each key fits in a respectivekeyway 75 in each mold insert.

To cast the assembly shown in FIGS. 1 and 2, th mold is closed to theposition shown in FIGS. 3, 4, and 7. Fluid plastic, say hot nylon, isinjected through a tube 76 into filling opening 57 of the mold. Thefluid plastic flows through passage 58, channel 60, and into the annularspace between the inner and outer annular walls formed by the plates andthe two mold inserts. Plastic also flows through the flow opening 62 inthe inner annular Wall on the first mold insert and fills the annularspace between the inner annular wall and the injection pins.

After the mold is full of plastic, injection is stopped and the mold isallowed to cool until the plastic reaches a solid but elastic state.Then, and before the plastic takes its final set of maximum rigidity,the first and second blocks are pulled apart in the direction of thearrows 23 in FIG. 3. As the plates are pulled apart, ejection pin 66 inthe second mold insert is pushed to the left (as viewed in FIG. 4) byconventional automatic means (not shown) to eject the flange and lipfrom recesses 68 and 70 in the second mold insert. The plastic issufficiently elastic to permit the required deformation, and yet returnsimmediately to the original shape cast in the mold. The plates remain inthe position shown in FIG. 5, but are now free to slide apart in theguide groove 53. The plates are pulled apart to release the periphery ofthe roller, and shear the plastic in the inclined channel 60 from theroller. Ejection pin 36 in the first block is pushed to the right (asviewed in FIG. 4) to eject the shaft flange and lip formed in the firstmold insert. The plastic is still of sufificient elasticity that theflanges and lips on the shaft can be ejected from the mold even thoughconsiderable deformation is required. The plastic has adequate memory toreturn to the original cast position once the part is free of the moldso that the assembly has the exact shape shown in FIGS. 1 and 2. Thethin plastic web in flow opening in the inner annular wall is shearedduring this operation and the roller is free to rotate on the shaft.

Thus, a roller can be permanently cast on a shaft without requiring anyassembling step, and without requiring special molds which require aplurality of complicated and expensive parts to release undercutportions of molded articles.

Of course the roller can assume a variety of shapes, and need not have aconcave periphery. For example, as shown in FIG. 9, a roller 78 has aconvex periphery 79 when the assembly is to be used as a wheel, or thelike.

I claim:

1. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body defining a hole, an annular inner wall in thehole and disposed around a portion of the hole to form a portion of alongitudinal shaft cavity, means supporting the annular inner wall -tobe spaced from the surface of the hole, means closing each end of theshaft cavity, said supporting means defining a first undercut recessbeyond one end of the inner wall, the first recess communicating withthe shaft cavity and extending outwardly past the inner wall to define afirst flange cavity, said supporting means defining a second undercutrecess beyond the other end of the inner wall, the second recesscommunicating with the shaft cavity and extending outwardly past theinner wall to define a second flange cavity, an outer annular walldisposed around and spaced outwardly from the inner wall to define aroller cavity between the two walls, and

channel means in the mold for disposing cast material in the shaft androller cavities.

2. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body defining a hole, an annular inner wall in thehole and disposed around a portion of the hole to form a portion of alongitudinal shaft cavity, means supporting the annular inner wall to bespaced from the surface of the hole, means closing each end of the shaftcavity, said supporting means defining a first annular undercut recessbeyond one end of the inner wall, the first recess communicating withthe shaft cavity and extending outwardly past the inner wall to define afirst flange cavity, said supporting means defining a second undercutrecess beyond the other end of the inner wall, the second recesscommunicating with the shaft cavity and extending under and outwardlypast the inner wall to define a second flange cavity, a separate annularlongitudinally extending recess formed around and joining the peripheryof each flange cavity, an outer annular wall disposed around and spacedoutwardly from the inner wall to define a roller cavity between the tWowalls, and channel means in the mold for disposing cast material in theshaft and roller cavities.

3. A mold for casting a shaft disposed Within an axial bore of a roller,the mold comprising a body defining a hole, an annular inner wall in thehole and disposed around a portion of the hole to form a portion of alongitudinal shaft cavity, means supporting the annular inner wall to bespaced from the surface of the hole, means closing each end of the shaftcavity, said supporting means defining a first undercut recess beyondone end of the inner wall, the first recess communicating with the shaftcavity and extending outwardly past the inner wall to define a firstflange cavity, said supporting means defining a second undercut recessbeyond the other end of the inner wall, the second recess communicatingwith the shaft cavity and extending outwardly past the inner wall todefine a second flange cavity, an outer annular wall disposed around andspaced outwardly from the inner wall to define a roller cavity betweenthe two walls, a plurality of ribs on the exterior of the inner wall toextend into the roller cavity, and channel means in the mold fordisposing cast material in the shaft and roller cavities.

4. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body defining a hole, an annular inner wall in thehole and disposed around a portion of the hole to form a portion of alongitudinal shaft cavity, means supporting the annular inner wall to bespaced from the surface of the hole, means closing each end of the shaftcavity, said supporting means defining a first undercut recess beyondone end of the inner wall, the first recess communicating with the shaftcavity and extending outwardly past the inner wall to define a firstflange cavity, said supporting means defining a second undercut recessbeyond the other end of the inner wall, the second recess communicatingwith the shaft cavity and extending outwardly past the inner wall todefine a second flange cavity, an outer annular wall disposed around andspaced outwardly from the inner wall to define a roller cavity betweenthe two walls, a plurality of radially spaced and longitudinal ribs onthe exterior of the inner wall to extend into the roller cavity, andchannel means in the mold for disposing cast material in the shaft androller cavities.

5. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body defining a hole, an annular inner wall in thehole and disposed around a portion of the hole to form a portion of alongitudinal shaft cavity, means supporting the annular inner wall to bespaced from the surface of the hole, means closing each end of the shaftcavity, said supporting means defining a first undercut recess beyondone end of the inner wall, the first recess communicating with the shaftcavity and extending outwardly past the inner wall to define a firstflange cavity, said supporting means defining a second undercut recessbeyond the other end of the inner wall, the second recess communicatingwith the shaft cavity and extending outwardly past the inner wall todefine a second flange cavity, a convex outer annular wall disposedaround and spaced outwardly from the inner wall to define a rollercavity between the two walls, and channel means in the mold fordisposing cast material in the shaft and roller cavities.

6. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body defining a hole, the body having a fillingchannel extending from its exterior to the hole, an annular inner wallin the hole and disposed around a portion of the hole to form a portionof a longitudinal shaft cavity, means supporting the annular inner wallto be spaced from the surface of the hole, means closing each end of theshaft cavity, said supporting means defining a first undercut recessbeyond one end of the inner wall, the first recess communicating withthe shaft cavity and extending outwardly past the inner wall to define afirst flange cavity, said supporting means defining a second undercutrecess beyond the other end of the inner Wall, the second recesscommunicating with the shaft cavity and extending under and outwardlypast the inner wall to define a second flange cavity, an outer annularwall disposed around and spaced outwardly from the inner wall to definea roller cavity between the two walls, and channel means fortransferring material to be cast from the filling channel to the shaftand roller cavities.

7. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body defining a hole, an annular inner wall in thehole and disposed around a portion of the hole to form a portion of alongitudinal shaft cavity, the inner wall having a flow opening throughit, means supporting the annular inner wall to be spaced from thesurface of the hole, means closing each end of the shaft cavity, saidsupporting means defining a first undercut recess beyond one end of theinner wall, the first recess communicating with the shaft cavity andextending outwardly past the inner wall to define a first flange cavity,said supporting means defining a second undercut recess beyond the otherend of the inner wall, the second recess communicating with the shaftcavity and extending outwardly past the inner wall to define a secondflange cavity, an outer annular wall disposed around and spacedoutwardly from the inner wall to define a roller cavity between the twowalls, and channel means in the mold for disposing cast material in theshaft and roller cavities.

8. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body including first and second blocks havingopposing surfaces adapted to fit closely together, each block having alongitudinal opening extending through it and opening at one end out ofa respective said opposing surface so when the block surfaces are fittedtogether the longitudinal openings in each block cooperate to form'ahole, an annular inner Wall in each block opening, the adjacent ends ofeach inner wall abutting around a portion of the hole to form a 1011-gitudinal shaft cavity, means supporting each annular inner wall to bespaced from the surface of the hole in its respective block, meansclosing each end of the shaft cavity, said supporting means defining aseparate undercut recess beyond the respective outer end of each innerwall, each recess communicating with the shaft cavity and extendingoutwardly past the inner wall to define a separate flange cavitycommunicating with the shaft cavity and extending under and outwardly ofthe inner wall, an outer annular wall disposed around and spacedoutwardly from the inner walls to define a roller cavity, and channelmeans in the mold for disposing cast material in the shaft and rollercavities.

9. A mold for casting a shaft disposed within an axial bore of a roller,the mold comprising a body including first and second blocks havingopposing surfaces adapted to fit closely together, each block having alongitudinal opening extending through it and opening at one end out ofa respective said opposing surface so when the block surfaces are fittedtogether the longitudinal openings in each block cooperate to form ahole, an annular inner wall in each block opening, the adjacent ends ofeach inner wall abutting around a portion of the hole to form alongitudinal shaft cavity, means supporting each annular inner wall tobe spaced from the surface of the hole in its respective block, meansclosing each end of the shaft cavity, said supporting means defining aseparate undercut recess beyond the respective attached end of the innerwall, each recess extending outwardly past the inner wall to define aseparate flange cavity communicating with the shaft cavity and extendingunder and outwardly, and a pair of plates disposed between the blocks tobe movable toward and away from each other on opposite sides of the holeso that adjacent edges of the plates can be moved into abutment witheach other, the adjacent edges of the plates each having a recess aroundthe hole in the block to form an outer annular wall disposed around andspaced outwardly from the inner walls to define a roller cavity, andchannel means in the mold for disposing cast material in the shaft androller cavities.

10. A mold for casting a shaft disposed within an axial bore of aroller, the mold comprising a body including first and second blockshaving opposing surfaces adapted to fit closely together, each blockhaving a longitudinal opening extending through it and opening at oneend out of a respective said opposing surface so when the block surfacesare fitted together the longitudinal openings in each block cooperate toform a hole, a separate pin disposed in each longitudinal opening tomake a close sliding fit, a separate annular inner wall in each blockopening, the adjacent ends of each inner wall abutting around a portionof the hole to form a longitudinal shaft cavity, means supporting eachannular inner wall to be spaced from the surface of the hole in itsrespective block, means closing each end of the shaft cavity, saidsupporting means defining a separate undercut recess beyond therespective attached end of the inner wall, each recess extendingoutwardly past the inner wall to define a separate flange cavitycommunicating with the shaft cavity and extending under and outwardly,an outer annular wall disposed around and spaced outwardly from theinner walls to de fine a roller cavity, and channel means in the moldfor disposing cast material in the shaft and roller cavities.

11. Apparatus according to claim 10 in which the inner ends of the pinsabut each other and are of reduced diameter to form a bore through theshaft cast in the mold.

References Cited UNITED STATES PATENTS 1,270,008 6/1918 Cobb 2643181,475,463 11/1923 Weida 264-241 1,916,692 7/1933 Scribner 2643183,077,637 2/1963 Peirkii et al. 264-318 3,206,992 9/1965 Ferdig 2642423,243,490 3 1966 Ulmschneider 2643 18 I. SPENCER OVERl-IOLSER, PrimaryExaminer.

R. D. BALDWIN, Assistant Examiner.

